My c2100UZ shows the zoom as a vertical bar to the left of the screen.

If I set digital zoom an extra bit of bar appears.

I only want to use digi on rare occasions. Can I keep it set to on but only zoom to the normal zoom bar .. Well of course I can. But should the pictures be the same quality as if no digital zoom was showing..

Or more simply.. does the poor digital zoom quality only kick in if i go over into that bar or does it kick in all the way from the bottom because i selected gigi zoom

Digital Zoom (DZ) is employed only when the
zoom indicator is in the red. However, once
past about 8x optical zoom, even with IS on,
photos will tend to blur plus chromatic
abberation (CA) tends to become more apparent.

The blur is caused predominantly by motion.
Either use a tripod and/or increase the shutter
speed (eg, set camera to sport mode).

Advice is to always stay in the optical zone
&amp; preferably &lt;=8x zoom. Photographing while
zoomed beyond 10X (ie, in the DZ region) will
aggrevate blur &amp; CA, but DZ has its place.
For example, use full 27x zoom with the EVF
as a telescope.(For surveillance purposes you
may want to get the make &amp; license number of
a vehicle 100 yards away using full (27x) zoom,
but don't expect to get photo quality that you
would be proud of posting as PIX of the day. The miracle accomplished was that you obtained a legible photograph of an auto's license at 100 yards!)

If you must DZ, then a better effect will
probably be achieved thru post process in
Photoshop.

If your picture is over 380mm, then you are using the digital zoom. You can check this by looking at the Properties of a single JPEG image file.

My experience is that with the digital zoom enabled, sometimes you are over 380 when on the line, and sometimes not. Unless you NEED the digital zoom, I'd recommend turning it off; in that way, any picture you take is just as sharp and clear as the lens can provide. If you really want to leave it on, I'd make sure the indicator is below, and not touching the white/red interface.